On 03/15/2016 01:59 PM, Stefan Roese wrote: > This patch changes the USB port scanning procedure and timeout > handling in the following ways: > > a) > The power-on delay in usb_hub_power_on() is now reduced to a value of > max(100ms, "hub->desc.bPwrOn2PwrGood * 2"). The code does not wait > using mdelay, instead usb_hub_power_on() will wait before querying > the device in the scanning loop later. The total timeout for this > hub, which is 1 second + "hub->desc.bPwrOn2PwrGood * 2" is calculated > and will be used in the following per-port scanning loop as the timeout > to detect active USB devices on this hub. > > b) > Don't delay the minimum delay (for power to stabilize) in > usb_hub_power_on(). Instead skip querying these devices in the scannig > loop until the delay time is reached. > > c) > The ports are now scanned in a quasi parallel way. The current code did > wait for each (unconnected) port to reach its timeout and only then > continue with the next port. This patch now changes this to scan all > ports of all USB hubs quasi simultaneously. For this, all ports are added > to a scanning list. This list is scanned until all ports are ready > by either a) reaching the connection timeout (calculated earlier), or > by b) detecting a USB device. This results in a faster USB scan time as > the recursive scanning of USB hubs connected to the hub that's currently > being scanned will start earlier. > > One small functional change to the original code is, that ports with > overcurrent detection will now get rescanned multiple times > (PORT_OVERCURRENT_MAX_SCAN_COUNT). > > Without this patch: > starting USB... > USB0: USB EHCI 1.00 > scanning bus 0 for devices... 9 USB Device(s) found > > time: 20.163 seconds > > With this patch: > starting USB... > USB0: USB EHCI 1.00 > scanning bus 0 for devices... 9 USB Device(s) found > > time: 1.822 seconds > > So ~18.3 seconds of USB scanning time reduction. > > Signed-off-by: Stefan Roese <s...@denx.de> > Acked-by: Hans de Goede <hdego...@redhat.com> > Tested-by: Stephen Warren <swar...@nvidia.com>
This breaks DWC2 on SoCkit, I can no longer detect any USB device. USB works without this patch though. Ideas? Best regards, Marek Vasut _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
